Recently, there has been a requirement for promoting non-volatilization of a system internal memory, and there has been suggested a MRAM (Magnetoresistive Random Access Memory) which uses a Tunneling Magnetoresistive (TMR) effect. The MRAM includes a MTJ (Magnetic Tunnel Junction) device at an intersection point between a word line and a bit line, and the MTJ device stores one-bit information. This MTJ device 9, as depicted in FIG. 58 and FIG. 59, serves as a laminated film in which a tunnel barrier layer is formed by interposing an insulating layer 96 between two ferromagnetic layers 95 (95a and 95b). In the MTJ device 9, when the magnetization directions of the two ferromagnetic layers 95 are identical with each other, electric resistance is low (see FIG. 58), whereas when the magnetization directions are different from each other, electric resistance is high (see FIG. 59). Thus, “0” and “1” of memory devices are determined depending on the magnetization directions and used as data.
The MTJ device 9 is formed by forming the ferromagnetic layer 95b on a substrate, forming the insulating layer 96 serving as the tunnel barrier layer thereon, and then forming the ferromagnetic layer 95a. Metal films are used as the ferromagnetic layers 95, and a metal oxide film is used as the insulating film 96. The metal films are formed mainly by sputtering. Further, the metal oxide film is formed, for example, by forming a metal film by a sputtering device and then oxidizing the metal film with oxygen radicals by another device. Therefore, in order to form the MTJ device 9, vacuum chambers or chambers for oxidation are needed corresponding to the number of laminated metal films or metal oxide films.
In paragraph [0068] of International Publication No. WO2009/060540, as a device that forms such a laminated film, there is suggested an inline-type wafer transfer device in which transfer chambers and process modules are connected with each other alternately. In this device, an arm within the transfer chamber receives a wafer from an upstream process module of the transfer chamber and delivers the wafer to a downstream process module of the transfer chamber. As such, a substrate is transferred through the process modules. Further, in Japanese Patent Laid-open Publication No. 2003-060008, there is described a technology of forming a laminated film of metal films by a device in which multiple processing units are connected around a second transfer chamber set to a vacuum atmosphere. In this configuration, two second transfer arms provided within the second transfer chamber load and unload a substrate with respect to the processing units.
In the case of manufacturing the MTJ device 9 by a single device, processing chambers corresponding to the total number of laminated metal films and metal oxide films are provided in the device. Further, substrates are continuously loaded into the device and transferred in sequence from an upstream processing chamber to a downstream processing chamber, and a series of processes for forming the laminated films are performed.
However, when the device is operated, the processing chambers provide in the device may break down and thus may not be applicable. In this case, a process of the broken processing chamber cannot be performed to the substrate loaded within the broken processing chamber and the substrates loaded into the device after the corresponding substrate, so that the laminated film cannot be formed by the device, and these substrates may be discarded.
Further, if the processing chamber breaks down, the operation of the device is stopped first, so that the series of processes performed to the substrates within the device are interrupted. Therefore, a series of processes can be continued with respect to the substrates loaded into the device before the substrate loaded within the broken processing chamber when the device is recovered and the series of processes are resumed. However, if the processes are stopped, a surface of a metal film is oxidized and MR (magnetic resistance)/RA (resistance) may be changed. As such, electric characteristics may be deteriorated. For this reason, even if the device is rapidly recovered and the processes are resumed, the corresponding substrate may be discarded. Since a device becomes precise and there has been a tendency to form a very expensive device on a substrate, there has been a demand for a vacuum processing device capable of reducing the number of discarded substrates while suppressing a decrease in throughput.
Neither International Publication No. WO2009/060540 nor Japanese Patent Laid-open Publication No. 2003-060008 does not describe a breakdown of a processing module and cannot solve a problem occurring when a processing module cannot be used. Further, even if a standby processing module that performs the process corresponding to that performed in the broken processing module is provided in the device described in International Publication No. WO2009/060540, a substrate is transferred through the process modules in this device. As a result, a transfer route for a substrate toward the corresponding standby process module becomes very complicated. Further, when the process modules are operated, the transfer of substrate is restricted, so that the throughput is decreased.
In the device described in Japanese Patent Laid-open Publication No. 2003-060008, the number of the processing chambers which can be connected to the second transfer chamber is limited, so that it is difficult to connect standby processing chambers to the second transfer chamber. Further, multiple transfer arms are provided within the second transfer chamber, but a substrate cannot be delivered within the second transfer chamber, and, thus, the substrate is transferred through the processing chambers. For this reason, in common with International Publication No. WO2009/060540, a transfer route for a substrate becomes very complicated, so that the throughput is decreased.